I´ve been looking around for others with the same problem.
I successfully jb´d my iPhone 4 (03.10.01) and after a few tries it worked fine. Then I tried with the iPad, the computer froze, nor the keyboard or touchpad worked and I had to do a hard shutdown.
When I started up again the Mail.app was screwed up.

Tried again with a 3gs and the computer froze again, didn´t f-up the mail this time though!

Anybody else have this happen?

Why would it be?

I used the mirror in the Member written news thread about GP.
Would be nice to get the iPad Jb´d!